Amsterdam experiment in mixing pedestrians, trams and bicycles, The

Institute of Transportation Engineers. ITE Journal, Aug 1999 by Zacharias, John

These questions are addressed in a field study of the Leidsestraat, a major pedestrianized street in the historic core of Amsterdam.

RESEARCH METHODS

In this feature, we examine the patterns of movement as they appear over time and in relation to the plan of the street. We show how the various identifiable streams of movement (eight of them) use various parts of the street surface, overlap, expand and contract. Secondly, we discuss the role of environmental design in the behavior of pedestrians and cyclists. Finally, we consider how variations in density impact on the space available for cyclists.

Our method involved videotaping sections of the street from elevated positions on bridges with a digital camera. Midday samples were taken at three sections of the street, each with the same cross-sectional design but with different intersection configurations and different pedestrian volumes.

The tape was sampled in single frames taken at sufficient intervals so that all the pedestrians in the earlier frame had been replaced in the later one. The section of the street represented in the frame was reproduced as a computer-based drawing. Individual pedestrians, bicycles and trams in the frame were plotted on the plan. In this way 45 frames were selected from the video record for detailed consideration. These layered maps are then reproduced as density diagrams to reveal the directionality of the flows and the intensity of use of various parts of the available channel.

Finally, we approach the question of the impact of an increase in pedestrian and cyclist presence by considering the behavior of individuals at the various recorded density levels. When the overall density is higher, is there a concomitant tendency for individuals to spread themselves over the available space or do they tend to reduce the amount of space between them within the channels already heavily used? For example, Liu8 found that the width of the channel used by cyclists is linearly related to the flow rate. However, pedestrians tend to spread out to gain greater physical and psychological comfort. As a result, it may be that relatively low overall pedestrian densities will present the cyclist with as difficult an obstacle course as a street with higher density. To find out what effect higher pedestrian density had on the maneuvering capability of the cyclists, we measured the distance between each individual and the three nearest individuals in each frame. The figures for pedestrians and cyclists were compared with overall densities.

THE LEIDSESTRAAT CASE STUDY

The Leidsestraat is a particular case but typical for the questions raised by such de facto shared pedestrian corridors. The street is officially pedestrianized and directly linked with the most heavily traveled parts of the central walking system, including the Kalverstraat and Nieuwendijk (Figure 1). These latter streets are narrower with higher overall flow levels and no bicycles except in off-peak hours. The Leidsestraat is the most important north-south transportation corridor through the city, at least until the north-south metro line is completed.